Pierre-Alain Joye has a quick post with a congratulations to the entire team (and testers, etc) that worked to get PHP 5.1.3 out the door.

He also specifically mentions two GD updates that were made to this new release - new compression filtering for the imagepng functionality, and a "weak mode" for imagejpeg. This new mode can be set in your php.ini file or with ini_set (gd.jpeg_ignore_warning).

To grab the latest PHP update, including these new features to the graphics libraries, head over to the main PHP site.